Comparing Lengths: Writing Equations

This lesson teaches how to compare lengths by writing equations. It covers using real objects, bars, and number lines to measure and compare lengths. Practical examples demonstrate setting up and solving equations for both subtraction and addition. The lesson concludes with a review of key concepts.

How do you find the difference in length between two pencils using erasers?

• Divide the length of the longer pencil by the shorter one.

• Subtract the length of the shorter pencil from the longer one.

• Add the lengths of both pencils.

• Multiply the lengths of both pencils.

What is a common misunderstanding when setting up equations to compare lengths?

• Using addition instead of subtraction.

• Placing the missing number in the wrong position.

• Using multiplication instead of division.

• Forgetting to draw a bar for each length.

If a board is 11 feet long and 3 feet are cut off, how long is the remaining piece?

• 7 feet

• 8 feet

• 14 feet

• 9 feet

How long will Reggie's driveway be if it is extended by 5 meters from its original length of 8 meters?

• 10 meters

• 13 meters

• 12 meters

• 15 meters

How much did Lewis grow from grade 1 to grade 2 if he was 47 inches tall in grade 1 and 53 inches tall in grade 2?

• 4 inches

• 7 inches

• 6 inches

• 5 inches